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The word "Must" or the word "Can" indicates Total Participation

The question is from a test series I took online and the auto check feature of the test say the correct answer is option B to which I disagree. According to me, the correct answer should be option C.

The test Question is,

A student can take one or more courses and courses can be offered to any number of students. Which of the following represents given scenario in ER-model?

Test Answer options are as follows.

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I think, either the answer given by auto check feature of the test is wrong or English grammar used to form this question is wrong. Nowhere in question, it is stated that the student must participate in course. Then how can the answer be B, indicating Total Participation.

According to me, if the statement reads:

"A Student can take one or more courses..."

Then answer should be C i.e. a student may have option not to participate. Because the word "can" does not mandate you to select in any case one entity.

According to me, if they (test takers) want answer C to be correct, then they should have wrote:

"A Student must take one or more course".

Can anyone throw some light here? Am I correct, or my concept is wrong? I am relatively new to DBMS, but I have gone through concepts thoroughly.

Solution

  • The question language is ambiguous. "X can Y" can mean "X can Y, but doesn't have to" or "X can Y, and nothing else". "May" has the same problems. In good technical documentation such words get defined clearly.

    You seem to expect "can" for the first & "must" for the second. Maybe the presentations by the test writers use "can optionally" for the first & "can" for the second. Maybe they just didn't notice that it is ambiguous. Maybe they agree with you & they meant the answer to be C.

    Find the presentations that the testers are testing. The words that the testers use mean what the testers say they mean.